Chemistry / CALCULATOR

Activation Energy from Two Rates

Activation Energy from Two Rates: explore an explicit model with input checks, a formula and a worked example.

Runs on your deviceUpdates as you typeFormula & example ↓
01

Your inputs

Adjust the values to explore a different result.

Enter rate constant k₁.
K
Enter temperature t₁ in K.
Enter rate constant k₂.
K
Enter temperature t₂ in K.

Formula

Ea=R ln(k₂/k₁)/(1/T₁−1/T₂).
  • Use the units shown beside each field.
  • Results update automatically whenever you change an input.
  • Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations use standard floating-point arithmetic; exact integer and fraction tools identify their own precision rules.
  • Two-point Arrhenius model; rate constants must have matching units and reaction order. Signed apparent energies are allowed.

Example Calculation

Example inputs
  • Rate constant k₁: 1
  • Temperature T₁: 300 K
  • Rate constant k₂: 2
  • Temperature T₂: 330 K

Doubling k between 300 K and 330 K gives about 19.02 kJ/mol.

Frequently asked questions

How do I use this calculator?

Enter rate constant k₁, temperature t₁, rate constant k₂, temperature t₂. The result updates automatically. Use Reset to restore the example values.

What method does it use?

Ea=R ln(k₂/k₁)/(1/T₁−1/T₂).. Two-point Arrhenius model; rate constants must have matching units and reaction order. Signed apparent energies are allowed.

Why might a rounded result differ?

The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.

Are my inputs saved online?

No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.

Check the assumptions and units before using this result. Read about calculation methods.